Defining the impact of glycan-microdomains of the HIV-1 Env glycan shield

定义 HIV-1 Env 聚糖屏蔽的聚糖微结构域的影响

• 批准号: 10390397
• 负责人: JAN NOVAK
• 金额: $ 71.86万
• 依托单位: UNIVERSITY OF ALABAMA AT BIRMINGHAM
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-10 至 2026-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10390397
• 关键词: Affect; Area; Binding Sites; Bioinformatics; Biological; Biology; Complex; Data; Databases; Engineering; Epitopes; Exhibits; Future; Glycoproteins; Goals; HIV; HIV Envelope Protein gp120; HIV-1; Heterogeneity; Human Biology; Immune; Immune response; Immune system; Infection; Informatics; Intervention; Mannose; Methodology; Modeling; Molecular; Molecular Biology; Mutate; N-Glycosylation Site; Persons; Polysaccharides; Positioning Attribute; Process; Publications; Publishing; Recombinants; Research; Role; Sequence Analysis; Series; Site; Structure-Activity Relationship; Surface; Surface Antigens; Tertiary Protein Structure; Testing; Therapeutic; Time; Variant; Virus; Virus Replication; Work; base; design; dimer; experimental study; insight; molecular dynamics; molecular mass; neutralizing antibody; novel; pathogen; prevent; receptor; tool; viral transmission

ABSTRACT Human immunodeficiency virus 1 (HIV-1) is a major global pathogen, with 1.7 million new infections in 2019. The HIV-1 envelope glycoprotein (Env) is the sole virus-surface antigen. Env, a trimer of gp120/gp41 dimer subunits, is densely glycosylated by N-glycans. For the gp120 subunit, N-glycans contribute over 50% of its molecular mass and form a protective surface, the so-called “glycan shield”, that interacts with cellular receptors and the immune system and protects the virus from neutralizing antibodies (nAbs). Recently, the concept of an “evolving glycan shield” has been proposed, based on the sequence analysis of immune-escape variants that have lost some potential N-glycosylation sites (NGS) and gained others. Despite significant strides in understanding the biology of HIV-1 Env, the complexity and function of N-glycans at a molecular level are poorly understood. Based on our bioinformatics and experimental studies, we recently proposed that the Env glycan shield may be defined, and analyzed, as distinct structural glycan-microdomains. Using naturally occurring Env variants of a clade B virus, we analyzed the glycans surrounding the highly conserved N262 glycan, in the so- called high-mannose patch (HMP) near the apex of the Env trimer. These HMP glycans, comprised of different combinations of 4 to 6 NGS in the proximity of N262, appear to form a glycan working unit. Based on our published results and preliminary data, we hypothesize that Env outer domain, gp120 glycan shield, has structural components that can be defined as distinct structural glycan-microdomains. We propose to test our hypothesis in different clades of HIV-1 and their immune-escape variants by assessing structural and functional impacts of a range of N-glycan combinations that comprise Env glycan-microdomains. Specifically, we propose to determine how different NGS combinations of the N262-anchored HMP-microdomain across variants and clades influence Env functions (Aim 1), to probe the structural arrangement of different N262-glycan cluster NGS combinations in the context of functional recombinant Env trimers (Aim 2), and to assess the functional impacts of other potential glycan-clusters of the HIV-1 Env glycan shield (Aim 3). To accomplish these goals, we will use a combination of functional, bioanalytical, structural bioinformatics, and molecular dynamics simulation approaches. The results of these studies will test our proposed hypothesis on the functional impact of the structural components of the glycan shield, glycan-microdomains, and will determine how the varied compositions of these microdomains affect the function of the glycan shield. These data will advance our understanding of the molecular biology of HIV-1 and the factors that impact viral transmission and persistence. Ultimately, these studies will generate new information about Env vulnerabilities that can be exploited to develop future therapeutic approaches.

抽象的 人类免疫缺陷病毒 1 (HIV-1) 是全球主要病原体，2019 年新增感染病例达 170 万例。 HIV-1 包膜糖蛋白 (Env) 是唯一的病毒表面抗原。 Env，gp120/gp41 二聚体的三聚体 亚基，被 N-聚糖密集糖基化。对于 gp120 亚基，N-聚糖贡献超过 50% 分子质量并形成保护表面，即所谓的“聚糖盾”，与细胞受体相互作用 和免疫系统，并保护病毒免受中和抗体 (nAb) 的侵害。最近，一个概念 基于免疫逃逸变体的序列分析，提出了“进化聚糖盾” 失去了一些潜在的 N-糖基化位点（NGS）并获得了其他位点。尽管取得了重大进展 对 HIV-1 Env 的生物学了解甚少，N-聚糖在分子水平上的复杂性和功能还很有限 明白了。基于我们的生物信息学和实验研究，我们最近提出 Env 聚糖 屏蔽可以被定义和分析为不同的结构聚糖微域。使用自然发生的环境 针对 B 型病毒的变种，我们分析了高度保守的 N262 聚糖周围的聚糖，即 位于 Env 三聚体顶端附近的高甘露糖斑块 (HMP)。这些 HMP 聚糖由不同的 N262 附近的 4 至 6 个 NGS 的组合似乎形成了聚糖工作单元。基于我们的 已发表的结果和初步数据，我们假设 Env 外部结构域 gp120 聚糖屏蔽具有 可以定义为不同的结构聚糖微域的结构成分。我们建议 通过评估结构和免疫逃逸变体，在 HIV-1 的不同分支及其免疫逃逸变体中检验我们的假设 包含 Env 聚糖微结构域的一系列 N-聚糖组合的功能影响。具体来说， 我们建议确定 N262 锚定的 HMP 微域的不同 NGS 组合如何跨越 变体和进化枝影响 Env 功能（目标 1），以探测不同 N262-聚糖的结构排列 在功能性重组 Env 三聚体的背景下对 NGS 组合进行聚类（目标 2），并评估 HIV-1 Env 聚糖屏蔽的其他潜在聚糖簇的功能影响（目标 3）。为了完成这些 为了实现目标，我们将结合功能、生物分析、结构生物信息学和分子动力学 模拟方法。这些研究的结果将检验我们提出的关于功能影响的假设 聚糖屏蔽的结构成分，聚糖微域，并将决定不同的 这些微域的组成影响聚糖屏蔽的功能。这些数据将推动我们 了解 HIV-1 的分子生物学以及影响病毒传播和持久性的因素。 最终，这些研究将产生有关 Env 漏洞的新信息，可用于开发 未来的治疗方法。